Alter previous migration - drop DB and reprovision to apply change

This change is annoying but migrations is confused about the non-existence of a field which uniqueness depends upon. This change fixes it but requires dropping DB and reprovisioning.

For your convenience, these commands will drop the DB:
update pg_database set datallowconn = 'false' where datname = 'transit_indicators';
SELECT pg_terminate_backend(procpid) FROM pg_stat_activity WHERE datname = 'transit_indicators';
drop DATABASE transit_indicators ;